Related Experiment Video
Updated: May 28, 2026
09:12
Surgical Swine Model of Chronic Cardiac Ischemia Treated by Off-Pump Coronary Artery Bypass Graft Surgery
Published on: March 27, 2018
Outcomes after conversion in the Veterans Affairs randomized on versus off bypass trial
Dimitri Novitzky1, Janet H Baltz, Brack Hattler
1James A Haley Veterans Hospital and the University of South Florida, Tampa, Florida, USA. novitzky@aol.com
The Annals of Thoracic Surgery
|October 8, 2011
Summary
Patients converted from off-pump coronary artery bypass (OPCAB) surgery experienced worse short-term and long-term outcomes. Emergent conversions in OPCAB patients showed the worst 30-day composite outcomes.
Area of Science:
- Cardiovascular Surgery
- Surgical Outcomes Research
Background:
- The Randomized On versus Off Bypass trial noted higher conversion rates from off-pump coronary artery bypass (OPCAB) to on-pump cardiopulmonary bypass (CPB).
- This study investigated the clinical outcomes associated with these conversions.
Purpose of the Study:
- To explore the reasons for and outcomes following intraoperative conversions during coronary artery bypass grafting (CABG).
- To compare the adverse event rates between converted OPCAB patients, on-pump CPB patients, and non-converted OPCAB patients.
Main Methods:
- A prospective study of 2,203 elective and urgent CABG patients across 18 sites.
- Surgeons were randomized preoperatively, with conversions performed if clinically indicated.
- Data on conversion reasons and patient outcomes were collected prospectively and retrospectively.
Main Results:
- Converted OPCAB patients more frequently had right coronary disease and targets <1.5 mm.
- Conversions were elective (49.3%), urgent (27.2%), or emergent (23.5%).
- Converted OPCAB patients exhibited significantly higher 30-day composite adverse outcomes (17.5%) compared to CPB (5.7%) and non-converted OPCAB (5.5%) groups (p < 0.001). One-year outcomes were also worse than CPB patients (13.5% vs 7.1%, p = 0.02).
Conclusions:
- Off-pump coronary artery bypass patients requiring conversion face poorer 30-day and 1-year outcomes.
- Right coronary artery disease and small target vessels were associated with higher conversion rates.
- Emergent OPCAB conversions demonstrated a trend towards the worst 30-day composite outcomes.
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